1. Field of the Invention
The present application relates to input buffers, and more particularly, to input buffers with reference voltage mixing.
2. Description of the Prior Art
Generally, an input buffer on an integrated circuit receives an input from an external source and generates an output based on that input, the output being used within the integrated circuit. Existing single ended input buffers have a first input and a reference voltage. When the input signal exceeds the reference voltage, the output of the buffer will change (from low to high or high to low). Because the reference voltage is externally generated, it may be noisy or undergo some fluctuation. In such cases, the buffer output may switch erroneously.
Because the switch point of input buffer is tied to the reference voltage signal, variation in the voltage level of the reference voltage signal may result in switching at the wrong time—too early, too late, or outside of a timed switching window. Timing problems may result in corrupted data being propagated through the integrated circuit, or may result in a metastable state in which the buffer output oscillates or signals that are electrically connected to the input buffer oscillate.